The Analog I/O API makes use of the LinkIt Analog to Digital Converter (ADC) to convert continuous analog signals into discrete digital signals read from the assigned analog pin (see Table below), for

to read the voltage of a sensor. The process is used in reverse to convert discrete digital signals to a continuous analog signal for writing to an assigned pin. 

Table: The analog input and output pins

Please note the following:

• analogWrite() realizes analog output using PWM to drive hardware analog output.
• analogWriteAdvance() fine-tunes parameters for more accurate PWM control.

LinkIt ONE provides 3 analog inputs (A0 to A2) compared to 6 inputs (A0 to A5) on Arduino UNO. Although LinkIt ONE operates on 3.3V, the analog input still accepts 0 to 5V inputs and transforms them to the digital range 0 to 1023. 

LinkIt ONE provides 2 PWM outputs (D3, D9) compared to 6 outputs (D3, D5, D6, D9, D10, D11) on Arduino UNO. However, the output from LinkIt on D3 and D9 supports accuracy up to 13-bit. The bit accuracy effects the output frequency, with 1.6kHz offered at 13bit, 50.8kHz at 8bit and 800kHz at 4bit.